iNav 8.0.1 reports NO RC LINK when one exists via DJI Air Unit, and intermittently fails to arm and disarm

[undiplomatic]

Current Behavior

Power up the quad, DJI Air Unit, DJI controller. Attempt to arm, but OSD intermittently shows "Unable to Arm, No RC Link". Once link "stabalises" and quad arms, it then fails to disarm (scary!). Eventually it will disarm after waiting and retrying.

Switching Air Unit and iNav to SBUS Fast fixes the issue. Seems to be unique to when standard SBUS is used.

Steps to Reproduce

1. Bind DJI Air Unit 04 Pro, Goggles 3, Controller 3 (the controller shares the video link)
2. Configure iNav and Air Unit to use SBUS, select UART.
3. Check the Receiver tab to be sure iNav is responding to controller movements/buttons
4. Attempt to arm - fails with "No RC link" message even though Receiver tab shows stable link
5. Keep waiting and trying, eventually error goes away and quad arms
6. Attempt to disarm... no response
7. Check Receiver tab to confirm channel is in disarm range (it is, but still doesnt disarm, also no FS warnings present)
8. Switch Air Unit and iNav to SBUS Fast... problem gone

Expected behavior

Should arm and disarm reliably as the channel switch is pressed.

Suggested solution(s)

Additional context

I checked that the receiver tab is showing continious stable signal. It is. Checked black box to see if any error states are noted when it fails to disarm - found none.

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• FC Board name and vendor: goku f722 pro mini v2
• INAV version string: 8.0.1
• INAV/FLYWOOF722PRO 8.0.0 Jan 21 2025 / 16:15:10 (ec2106af)
• GCC-13.2.1 20231009

[DroneWuKong]

I having a similar issue in iNav 8 with mavlink rc....everything works....but it wont let me arm cause of the "no rc link" flag and I clearly have a link.

It flies fine via elrs...but rc over telemetry seems to be an issue.